Often used to describe a girl (plain or muscular), whether ill tempered or mellow with abnormal superhuman strength that defies all sense of logic and reason.
Kagura is holding the scooter down, preventing Gintoki to speed away.

Gintoki: Shinpachi, you’ve suddenly got a lot heavier.
Kagura: I’ve never seen a grown man abandon a girl being chased by the yakuza.
Gintoki: Well, I’m a boy at heart. And besides, in this country, we don’t call someone who can stop a scooter with her bare hands a girl. We call her a mountain gorilla.
by jackkanarchy99 January 24, 2011
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